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      <title>状态机让你的程序优雅100倍 - 交互式测验</title>
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    </head>
    <body>
      <div class="main-wrapper">
          <div class="quiz-container">
            <div class="quiz-header">
              <h1>状态机让你的程序优雅100倍 - 交互式测验</h1>
              <p>检验你对文档内容的理解程度</p>
            </div>
            <div id="quiz-content">
                <div class="quiz-body">
                    <div class="progress-bar">
                        <div id="progress-indicator"></div>
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                    <div id="question-container">
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                    <div id="hint-container" class="hint-container"></div>
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                  <button id="prev-btn" class="nav-btn">上一题</button>
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                </div>
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      </div>

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  {
    "question": "根据文档，构成有限状态机（FSM）最核心的三个基本元素是什么？",
    "options": [
      "对象、方法和属性",
      "状态、事件和转换",
      "变量、函数和循环",
      "输入、处理和输出"
    ],
    "correctAnswerIndex": 1,
    "explanation": "文档明确指出，有限状态机（Finite State Machine）由三个基本元素组成：状态（State）代表系统在特定时刻的情况；事件（Event）是触发状态变化的动作；转换（Transition）则定义了在特定状态下，由特定事件触发，系统会进入哪个新状态。这三者共同构成了状态机的核心。",
    "source": "文档中「一、状态机的基本概念」->「1. 什么是有限状态机(FSM)」部分",
    "hint": "文档中将这三个元素比作一张地图，其中状态是地点，事件是路径，转换则是旅程。"
  },
  {
    "question": "文档中强调，状态机与传统if-else编程的本质区别在于什么？",
    "options": [
      "状态机的代码执行效率总是更高",
      "编程思维方式的根本转变：从基于条件到基于状态",
      "状态机只能用面向对象的语言实现",
      "状态机代码的行数绝对更少"
    ],
    "correctAnswerIndex": 1,
    "explanation": "文档在对比两者时明确指出：“传统if-else是基于条件的编程，而状态机是基于状态的编程。这种思维方式的转变是本质区别。” 这意味着开发者关注的焦点从离散的、独立的条件判断，转移到了系统整体的状态流转上。",
    "source": "文档中「一、状态机的基本概念」->「3. 状态机与传统if-else的本质区别」部分",
    "hint": "思考一下编程时关注的焦点是什么，是孤立的条件判断，还是系统整体的生命周期？"
  },
  {
    "question": "根据「if-else地狱的真实面目」章节的描述，深层嵌套的if-else结构最令人头疼的问题之一是什么？",
    "options": [
      "导致代码编译时间过长",
      "无法处理异步逻辑",
      "需求变更时极易引发连锁反应，修改风险高",
      "会大量消耗服务器内存"
    ],
    "correctAnswerIndex": 2,
    "explanation": "文档以“需求变更时的连锁反应”为小标题，生动地描述了在复杂的if-else结构中，一个看似简单的需求变更（如增加一个检查步骤）可能需要修改多处代码，且很容易遗漏某个分支，从而使变更成为高风险操作。状态机通过状态隔离有效地缓解了这个问题。",
    "source": "文档中「二、if-else地狱的真实面目」->「3. 需求变更时的连锁反应」部分",
    "hint": "想象一下，当产品经理要求在某个流程中间增加一个步骤时，维护一个有23层嵌套条件的代码会发生什么。"
  },
  {
    "question": "文档提到了状态机设计的诸多核心优势，以下哪一项不属于文档中明确强调的优势？",
    "options": [
      "业务逻辑可以轻松地可视化为状态转换图，便于沟通",
      "将状态与行为明确分离，提升了代码结构的清晰度",
      "能自动优化数据库查询，提升数据读写性能",
      "状态间的隔离性提高了系统的稳定性，修改不易互相影响"
    ],
    "correctAnswerIndex": 2,
    "explanation": "文档在「三、状态机设计的核心优势」章节中，明确列举了三大优势：代码结构的清晰度提升、业务逻辑的可视化表达、以及状态隔离带来的稳定性。文档并未提及状态机本身具备自动优化数据库查询的能力。",
    "source": "文档中「三、状态机设计的核心优势」部分",
    "hint": "回顾第三章节的三个小标题，它们直接概括了状态机的核心优势。"
  },
  {
    "question": "当遇到一个特别复杂的业务（例如，订单处理中的“支付中”状态本身就包含验证、处理、完成等多个子步骤），文档推荐使用哪种进阶设计来应对？",
    "options": [
      "并行状态机",
      "持久化状态机",
      "分层状态机",
      "命令模式状态机"
    ],
    "correctAnswerIndex": 2,
    "explanation": "文档在「六、状态机设计的进阶」部分明确介绍了“分层状态机”。这种设计允许一个主状态（如“processingPayment”）内部再包含一个完整的子状态机，用于处理该状态下的复杂逻辑，从而有效地管理和分解复杂度。",
    "source": "文档中「六、状态机设计的进阶」->「1. 分层状态机处理复杂业务」部分",
    "hint": "文档中介绍了一种允许“状态内部再包含一个完整的状态机”的高级技巧。"
  },
  {
    "question": "根据文档「何时该用状态机，何时不该用」的建议，在下列哪种情况下引入状态机模式可能是一种“过度设计”？",
    "options": [
      "管理一个有明确审批流程的工单系统",
      "一个简单的开关功能，只有“开”和“关”两种状态",
      "实现一个网络通信协议（如TCP）的状态管理",
      "控制游戏中AI角色的行为（如巡逻、追逐、攻击）"
    ],
    "correctAnswerIndex": 1,
    "explanation": "文档在“过度设计的警告信号”一节中明确指出，当“状态很少（少于3个）且转换简单”时，使用状态机可能会显得过于复杂，即过度设计。对于只有两种状态的简单开关，使用一个布尔值和简单的if-else通常更直接、更易于理解。",
    "source": "文档中「七、何时该用状态机，何时不该用」->「2. 过度设计的警告信号」部分",
    "hint": "文档给出的“警告信号”之一与系统中状态的数量有关。"
  },
  {
    "question": "在重构订单处理系统时，文档展示了使用状态机模式后的一种常见实现方式，其核心思想是什么？",
    "options": [
      "将所有逻辑都写在一个巨大的process函数中，用switch-case代替if-else",
      "为每个状态创建一个独立的类（如NewOrderState, PaidOrderState），每个类只负责处理自己状态下的事件",
      "使用数据库存储过程来处理所有的状态转换逻辑",
      "将所有事件都放入一个队列，由一个单独的线程顺序处理"
    ],
    "correctAnswerIndex": 1,
    "explanation": "文档中的Java和Python重构示例都清晰地展示了状态模式的应用：为每个状态（如NewOrderState, PaidOrderState）创建一个对应的类。这个类封装了该状态下的所有行为和转换逻辑。当一个事件到来时，系统将事件委托给当前状态对应的对象来处理，从而实现了状态与行为的解耦和隔离。",
    "source": "文档中「四、订单处理系统的重构」部分（参考Java和Python示例）",
    "hint": "观察重构后的代码结构，特别是类（Class）是如何组织的。"
  }
];
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            const answeredCount = userAnswers.filter(a => a !== null).length;
            const wrongCount = answeredCount - correctCount;
            const skippedCount = totalQuestions - answeredCount;
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                '<h2>答题报告</h2>' +
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                '<div class="score-card">' +
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                '<div class="score-card">' +
                '<h3>错误率</h3>' +
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                '<div class="score-card score-details">' +
                '<table>' +
                '<tr><td>正确</td><td>' + correctCount + '</td></tr>' +
                '<tr><td>错误</td><td>' + wrongCount + '</td></tr>' +
                '<tr><td>未答</td><td>' + skippedCount + '</td></tr>' +
                '</table>' +
                '</div>' +
                '</div>' +
                '<div class="report-actions">' +
                '<button id="review-btn">回顾测验</button>' +
                '<button class="primary" onclick="location.reload()">再试一次</button>' +
                '</div>' +
                '</div>';

            let reportEl = document.querySelector('.final-score-container');
            if (reportEl) {
                reportEl.remove();
            }
            quizContentEl.insertAdjacentHTML('beforeend', finalScoreHtml);
            document.getElementById('review-btn').addEventListener('click', reviewQuiz);
        }

        function reviewQuiz() {
            const reportEl = document.querySelector('.final-score-container');
            if (reportEl) {
                reportEl.remove();
            }

            document.querySelector('.quiz-body').style.display = 'block';
            document.getElementById('quiz-footer').style.display = 'flex';
            
            currentQuestionIndex = 0;
            loadQuestion();
            updateNavigationButtons(); // Ensure nav buttons are correctly displayed
        }

        // Event Delegation for options
        optionsListEl.addEventListener('click', (event) => {
            if (event.target && event.target.matches('li.option-item')) {
                // Check if the question has already been answered
                if (userAnswers[currentQuestionIndex] === null) {
                    const selectedIndex = parseInt(event.target.dataset.index, 10);
                    selectOption(selectedIndex);
                }
            }
        });

        prevBtn.addEventListener('click', goToPreviousQuestion);
        nextBtn.addEventListener('click', goToNextQuestion);
        hintBtn.addEventListener('click', showHint);
        
        // 初始加载
        loadQuestion();
      </script>
    </body>
    </html>
  